It's kind of a reflex, from playing so many games that use WASD, I always have my finger on the key. My brain could be 90% in idle and there's one neuron in there that knows - W is to move forward, so I press it a lot.
I think it's more about 'unlinking' things in the mind. Cause it's clear in Rifter, but it's difficult to counter the reflex, especially when playing lots of games that use WASD.